Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual país tem uma pontuação de 68-70=138?
 ###Tabelas: CREATE TABLE second_round (second_round_id AUTO_INCREMENT PRIMARY KEY, Place VARCHAR, Player VARCHAR, Country VARCHAR, Score VARCHAR, To par VARCHAR) CREATE TABLE list_of_lighthouses_in_the_philippines (list_of_lighthouses_in_the_philippines_id AUTO_INCREMENT PRIMARY KEY, Lighthouse VARCHAR, Location VARCHAR, Province/City VARCHAR, Date First Lit VARCHAR, Tower height in ft (m) VARCHAR, Focal plane in ft (m) VARCHAR, Current Status VARCHAR, Current Condition/ Description VARCHAR) CREATE TABLE dos_shells (dos_shells_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Release date VARCHAR, Latest version VARCHAR, Status support VARCHAR, Source model VARCHAR, Architecture VARCHAR, Target market VARCHAR) CREATE TABLE all-time_playoffs_records_* (all-time_playoffs_records_*_id AUTO_INCREMENT PRIMARY KEY, Pts Rank VARCHAR, Club VARCHAR, Appearances vs Seasons VARCHAR, Appearances Percetages VARCHAR, PPG Rank VARCHAR) CREATE TABLE nine_pieces (nine_pieces_id AUTO_INCREMENT PRIMARY KEY, Standard order INT, English translation VARCHAR, Transcription (based on Pinyin) VARCHAR, Traditional Chinese VARCHAR, Simplified Chinese VARCHAR)  
SELECT Country FROM second_round WHERE Score = 68-70=138